1. Field of the Invention
This invention relates to couplers and especially to couplers providing hinged rotary relative motion for articulated elements.
2. Description of Related Art
Various coupling joints have been known and used in the past. Included among these is the device shown in U.S. Pat. No. 160,046, issued Feb. 23, 1875, to Wright. Wright shows a fame held together by double rings constructed with interior circumferential grooves extending partially through the rings and having through the rings an opening by which a pin may be introduced into the uprights and grooves. The grooves serve as guides for opening and closing the sections of the frame. U.S. Pat. No. 1,895,317, issued Jan. 24, 1933, to Genich, shows an automotive jack having a two-part handle and a connector. The connector has two parallel sockets for holding the handle halves together. U.S. Pat. No. 3,105,510, issued Oct. 1, 1963, to Demosthenes, shows a coupling for a water riser pipe and an anchoring and stabilizing pipe. The coupling comprises a one-piece casting having end portions with open end bores disposed in spaced parallelism and slidably embracing the riser pipe and stabilizing pipe, respectively.